Energy Management 101: Smart Submetering and Data Logging

Wish to be an energy whiz? Deploy devices that cut consumption, balance baselines, and revitalize reliability

You can’t manage what you don’t measure. And if you’re measuring your building up against today’s efficiency pacesetters, then data logging and submetering can take you the extra mile.

Data loggers and submeters will dive into greater detail about your energy consumption – more than a utility bill can ever hope. You can learn about usage on a floor, system, or fixture basis. Having this kind of granularity leads to small steps that can yield great strides.

First consider why and how you’ll best utilize these strategies, and then focus on slicing down the two biggest sections of the energy pie: HVAC and lighting. Unless you’re converting the data into actionable items, a logger or submeter is no more useful than a garage opener – which is about as easy to use. Read on and learn how to best utilize these new trinkets in your energy toolbox.

Motivation and Methodology
When confronting cutting-edge, tech-heavy strategies, some FMs face quandaries. But the two most important questions to ask are why and how.

“Knowing what to do means making predictions with less ambiguity and uncertainty,” says Matt Ganser, director of engineering for Carbon Lighthouse, a firm that helps clients achieve carbon neutrality. “That answer is data.”

Facilities professionals want to reduce costs, keep occupants happy, and optimize equipment performance. Achieving these goals requires knowing the building’s pulse, and you can take it with loggers and meters.

“Recording actual energy usage at a more granular level can also be used to allocate specific costs to tenants based on their consumption,” explains Gregg Dixon, senior vice president of sales and marketing for EnerNOC, a provider of energy intelligence software. “Compliance with certain green building initiatives and certifications may also require submetering.”

Once you’ve addressed the motivation behind your deployment, you can move on to the method of performing it.

“A caveman couldn’t do it, but basically any person can launch and deploy a couple loggers every minute. The technology shouldn’t be a barrier,” Ganser says. “The trick is knowing what to measure.”

In addition to energy consumption, loggers and meters can record temperature, humidity, carbon dioxide, water use, light levels, and several other metric. For most applications, intervals of 15 minutes over a one-month period are sufficient.

The devices can be secured via magnetic backing or duct tape. Make sure they are in secure locations that are out of the way. Ask staff, security, and tenants not to move them. “Tell them they’re part of an intensive energy investigation,” recommends Ganser.

Your device will either feed into a central logger/meter or connect to a computer or tablet via the Internet. Using the provided interface, choose a common start time for all devices and give each one a specific name. “A tip is to use a unique signifier based on location,” Ganser suggests. “Don’t just call it ‘temperature.’”

Have a working hypothesis at deployment. Think about when certain equipment should run and when the building is occupied. Consider if an environment is stuffy or drafty. Ask yourself what you’re specifically looking for and what you’re trying to prove. If you’re skeptical of system performance, your suspicions will likely surface in one of the following two areas.